KDiskFree

KDiskFree lists the storage devices and filesystems the system knows about and shows how full each one is. Every row carries the device name, filesystem type, total size, free space, percentage in use and mount point, together with a bar that makes a nearly full volume obvious without reading the numbers. The list refreshes on an interval, so a partition can be watched while something writes to it.

Rows can be acted on directly: a mounted filesystem can be unmounted and an unmounted one mounted, and a mount point can be opened in the file manager or in a terminal. Which columns appear, how often the list refreshes, and the threshold at which a volume is treated as nearly full are all configurable.

The program answers the question of which volume is running out of room, not which files are responsible for it. Breaking a single filesystem down per directory is the job of a disk usage analyser instead. KDiskFree is part of the KDE utilities and reads the system's table of mounted filesystems.